Printers and recorders of various types have been developed which employ a stream of ink droplets. The ink is expelled through a small opening as a result of the action of a transducer. A cavity is formed that is partially enclosed by flexible diaphragm backed by a piezo-electric material to form a chamber. The piezo-electric material has the ability to change shape upon being charged electrically. A channel leads from the chamber to the opening and another channel leads to the chamber so that ink may be supplied thereto. A small charge is applied to the piezo-electric material to alter its shape and thereby cause a drop of ink to be ejected from the chamber and out the opening. In prior devices, the transducer was composed not only of a piezo-electric material but also had a diaphragm layer between the chamber and the piezo-electric material. The diaphragm was made of a conductive material such as metal and was used to control the movement of the piezo-electric material.
Although prior systems have worked substantially well, improvements are always sought. One goal consistently pursued is to have the openings of the ink jet printer as close to one another as possible. Obviously, by having the openings close together, one is able to produce more dots per unit area and obtain more refined printing. The barrier in having openings close together is the fact that each chamber of the ink jet printer that requires a minimum amount of space. Various designs have been developed in order to have the openings close together. One attempt is to have more lines of openings whereby the openings are staggered relative to one another to form two rows of openings. Although this has the advantage of having more openings per line, the disadvantage is that synchronization is required between the enabling of the piezoelectric elements and movement of the medium being printed so that a price must be paid in electronics. Another way of attempting to increase the density of openings is to have elongated chambers as opposed to circular chambers. The problem with this configuration is that one loses efficiency. Another scheme attempted is to have not only longitudinally-shaped chambers, but to put them in a fanning arrangement. The disadvantage with this configuration is not only the inefficiency as a result of having elongated chambers but also the chambers are further removed from the openings.